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Date:   Tue, 2 Jun 2020 08:01:41 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Anshuman Khandual <anshuman.khandual@arm.com>
Cc:     linux-mm@kvack.org, hughd@google.com,
        Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
        Zi Yan <ziy@nvidia.com>, John Hubbard <jhubbard@nvidia.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/vmstat: Add events for PMD based THP migration
 without split
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References: <1590118444-21601-1-git-send-email-anshuman.khandual@arm.com>
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On Fri, May 22, 2020 at 09:04:04AM +0530, Anshuman Khandual wrote:
> This adds the following two new VM events which will help in validating PMD
> based THP migration without split. Statistics reported through these events
> will help in performance debugging.
> 
> 1. THP_PMD_MIGRATION_SUCCESS
> 2. THP_PMD_MIGRATION_FAILURE

There's nothing actually PMD specific about these events, is there?
If we have a THP of a non-PMD size, you'd want that reported through the
same statistic, wouldn't you?